I don't really see how there is any doubt. The ball doesn't move and a sound isn't made in the right place for it to be bat. None of the technology picked up anything either.
As I said - I had the sound off. However, you are forgetting the umpire does not have the use of all of this technology at the exact MOMENT the ball is bowled - only at review. In real time it definitely could've looked like it COULD have taken a slight nick, therefore there is some doubt, and so, NOT OUT.